Adam Back, CEO of Blockstream and one of the few people actually cited in the Bitcoin whitepaper, is sounding the alarm on BIP-110. The proposal, which would restrict arbitrary data storage in Bitcoin transactions, is barreling toward its mandatory enforcement block height with almost nobody on board.
The two possible outcomes, according to Back: it either triggers a chain split around August 7th, or it simply fails to activate.
What BIP-110 actually does
BIP-110 wants to impose strict limits on non-monetary data, capping OP_RETURN outputs at 83 bytes and restricting data pushes to 256 bytes. It would make life significantly harder for protocols like Ordinals and Runes, which use Bitcoin’s block space to store images, tokens, and other data that purists consider “spam.”
The proposal originally surfaced as BIP-444 in late 2025 before being renumbered. It’s structured as a one-year soft fork, meaning its restrictions would be temporary. But the mechanism it uses to get there, a User Activated Soft Fork (UASF), is where things get dicey.
